1. Introduction

Putting to sea to fish has been a way of life and an important economic activity for millennia (e.g. Robinson 2013). However, archaeological evidence for specific types of offshore marine fishing is uncommon: the objects and vessels used were usually lost at sea or salvaged and re-used, and most of their components were organic and therefore have not survived (Beltrame 2010). Once-common kinds of fishing vessel have completely disappeared, leaving no historical description or archaeological trace (e.g. Hutchinson 1994, 142). Also, the technology employed in the past to fish for a particular catch almost never left direct physical marks on that catch, but has to be inferred from the size and habitat of the catch (Morales Muniz 2010; e.g. Barrett et al. 2004). The methods for drawing these inferences are quite developed for archaeological remains of consumed shellfish (Campbell 2008; e.g. Cabral and da Silva 2003; Kent 1992).

The common whelk, edible whelk or buckie (Buccinum undatum L., 1758) is one of the consumed shellfish found archaeologically. It is a marine gastropod of the cold North Atlantic (Hayward and Ryland 1995, 685–86); its shell is large (up to 165mm: Jeffreys 1867, 287), spiral, and sharply conical, with a prominent, open siphonal canal at its base and a distinctive undulating surface with fine spiral ribs (Figure 1). Whelks are highly mobile carnivore-scavengers found across all types of sea-bed, from the low inter-tidal to deeper coastal waters (Fretter and Graham 1962, 517–19) down to 1200m (Hayward and Ryland 1995, 686), but usually in waters between 15m and 30m deep (Valentinsson et al. 1999).

Figure 1
Figure 1: Shell of common whelk, Buccinum undatum L. ap: aperture; bw: body-whorl; cn: siphonal canal; lp: lip of aperture; sp: spire. (Image credit: amended from Dautzenberg and Fischer 1912, pl. 4)

Whelks can be fished by both methods of bottom-fishing, bottom-trawling (Mensink et al. 2000) and dredging (Hancock 1967, 4). In bottom-trawling, a roughly conical net, with its open end weighted and held open by some structure such as a wooden or metal beam (Figure 2a), is dragged ('trawled') behind a vessel along the surface of the sea-bed (Nédélec and Prado 1990, 25). In dredging, the structure holding the net open includes a bar at its base (Figure 2b) that scrapes the sea-bed (Nédélec and Prado 1990, 31). Dredging seems to be the older method, employed principally for oysters. Oyster-shells with shapes characteristic of uncrowded dredged beds, not natural reefs, are usual in Saxon (Winder and Gerber-Parfitt 2003), Roman (Winder 1985, 93) and prehistoric deposits (Milner 2002). Oyster-dredging has been regulated and taxed in England since the 12th century AD (Eyton 1858, 4). Bottom-trawls seem to have developed later; a Royal Commission was set up to investigate their introduction to England in AD 1376 (Engelhard 2008, 2). Bottom-fishing requires boats designed specifically for power, stability and sailing a steady course, and equipped with specialised gear for raising, lowering and surviving the dragging of heavy nets, and with a crew who know how to work that gear (McKee 1983, 40-41; Rawson and Tupper 2001, 689); its onset marks the emergence of a specialised marine fishing technology from general-purpose fishing.

Figure 2
Figure 2: Types of bottom-fishing gear. (a): bottom-trawl of beam-type (b): dredge. (Image credit: after Nédélec and Prado 1990)

Bottom-fishing damages the sea-bed (Kaiser et al. 1996) and its occupants (Jenkins et al. 2001), including the whelks themselves (Mensink et al. 2000), contributing to their local extermination (Cadée et al. 1995). Therefore, the usual method uses 'pots' of woven wicker or wire, baited with dead fish or carrion (Hancock 1967, 4-6), much like fishing for crab or lobster. This method has been used for whelks for generations (e.g. Jeffreys 1867, 289-90).

Whelks are relatively uncommon in archaeological sites in North Atlantic Europe. They are infrequent in the region's Palaeolithic, Mesolithic and Neolithic shell-middens (Gutiérrez-Zugasti et al 2011; e.g. Dupont 2006; Thomas and Mannino 1999, 96) including the classic examples in Denmark (Andersen 2008; e.g. Nielsen 2008). Whelks were brought to sites far inland in the British Neolithic: a large perforated shell was found at Windmill Hill (Smith 1965, 135). They are found occasionally in later prehistoric deposits (Bell 1977, 287), in Roman towns (O'Connor 1986, 8) and rural settlements (e.g. Cartwright 1982, 25), in Viking-era settlements in northern Britain (e.g. Milner et al. 2007, 1466; O'Connor 1984), in later Saxon English towns (e.g. Winder 1980, 125) and coastal sites (e.g. Murray 2001), and in medieval towns (Campbell 2011, 5; O'Connor 1984). The recent recovery of a sizeable number of whelks from a single well-stratified deposit at a well-understood site (Carisbrooke Castle) meant those whelks merited detailed analysis.